1. Technical Field
The apparatus relates to a surgical stapling apparatus, and more particularly, to an apparatus for sequentially applying a plurality of surgical fasteners to body tissue and optionally incising the fastened tissue.
2. Background of Related Art
Surgical devices wherein tissue is first grasped or clamped between opposing jaw structure and then joined by means of surgical fasteners are well known in the art. In some instruments a knife is provided to cut the tissue which has been joined by the fasteners. The fasteners are typically in the form of surgical staples however, two part polymeric fasteners are also utilized.
Instruments for this purpose can comprise two elongated members which are respectively used to capture or clamp tissue. Typically, one of the members carries a disposable cartridge which houses a plurality of staples arranged in at least two lateral rows while the other member comprises an anvil which defines a surface for forming the staple legs as the fasteners are driven from the cartridge. Generally, the stapling operation is effected by a pusher which travels longitudinally through the cartridge carrying member, with the pusher acting upon the staples to sequentially eject them from the cartridge. A knife may travel with the pusher between the staple rows to longitudinally cut and/or open the stapled tissue between the rows of staples. Such instruments are disclosed in U.S. Pat. Nos. 3,079,606 and 3,490,675.
A later stapler disclosed in U.S. Pat. No. 3,499,591 applies a double row of staples on each side of the incision. This is accomplished by providing a cartridge assembly in which a cam member moves through an elongate guide path between two sets of staggered staple carrying grooves. Staple drive members are located within the grooves and are positioned in such a manner so as to be contacted by the longitudinally moving cam to effect ejection of the staples. Other examples of such staplers are disclosed in U.S. Pat. No. 4,429,695.
Each of the instruments described above were designed for use in conventional surgical procedures wherein surgeons have direct manual access to the operative site. However, in endoscopic or laparoscopic procedures, surgery is performed through a small incision or through a narrow cannula inserted through small entrance wounds in the skin. In order to address the specific needs of endoscopic and/or laparoscopic surgical procedures, endoscopic surgical stapling devices have been developed and are disclosed in U.S. Pat. Nos. 5,040,715; 5,312,023; 5,318,221; and 5,326,013. In general, these instruments are provided with clamping structure to effect approximation of an anvil and a cartridge to secure tissue therebetween, and staple firing structure to effect sequential ejection of a plurality of fasteners from the cartridge after the tissue has been secured. It would be beneficial however, to provide an endoscopic stapling device having actuation structure configured to effect progressive approximation of an anvil and a cartridge concomitant with the sequential ejection of a plurality of fasteners from the cartridge.